With this warm weather, capsicum farmers better be on the lookout for powdery mildew. This is one of those dangerous fungal disease that spreads like bush fire in your fields. A severe infestation on your fields can cause a lot of damages to your expected yields.
This disease primarily affects leaves of the capsicums. Other parts mostly affected are stems and flowers. It occurs at any stage of crop development with the most common affected stage being the fruiting phase or just before onset of the fruiting phase.
If your crops are infected, you will notice a white, powdery growth (let's call them spores) on the leaves surface. Despite some similarities, this disease should not be confused with its counterpart, downy mildew. In downy mildew, this white powdery growth occurs on the lower surface of the leaves only while in powdery mildew it develops on both sides of the leaves. Also, downy mildew occurs during cold weather only and stops as warm weather kicks in.
Once a plant is infected with this powdery mildew, it is quite easy to spread to the other crops. All that is required is a little bit of wind and your entire capsicum field falls victim. Wind spreads the spores from one infected plant to the next one and within a short period of time you can have almost all crops in that field affected.
If left unchecked, this disease will cause discoloring and sometimes upward curling of leaves. They begin to turn yellowish or brownish and will eventually die and fall off the plant leaving the fruits exposed to the sunburns. This can render your crops unmarketable.
It is easy to prevent and cure this disease. All you have to do is monitor your crops and apply the following methods if you spot the disease.
One way is to use garlic mixed with liquid soap. This involves crushing the garlic to obtain its extracts and adding some few drops of the liquid soap. Once ready add water to the mixture such that 90% is water and 10% is the garlic and soap “concussion”. For a 1/4 acre of capsicums, you will need approximately a kilo of garlic and about a liter of the liquid soap. Crush the garlic to obtain the pulp, mix with the soap and add it to a 20 liter Jerry can.
Spray the solution to your infected crops once a week. This garlic solution prevents germination of the spores hence minimizing spread of the disease.
Another way is use of milk solution. If you happen to be milking, put some fresh cow milk in your spraying can and add water to the same ratio of 10% to 90% . Spray your crops with this solution once a week and powdery mildew spread will be eliminated.
Useof Neem oil is also a known measure. Once you notice the spores beginning to develop, mix Neem oil ( some 2 to 3 table spoons) with 5 liters of water and spray your crops once a week.
Also, given that the disease thrives on the dry surface of the leaves, overhead irrigation can suppress development of the spores hence controlling the disease spread.
If things seem to be getting out of hand, applying fungicides is highly recommended. As suggested by veteran farmers in MFarm, use of “Score” and “Bayleton” fungicides to spray your crops will help in eliminating the disease.
It is a good idea to alternate the above mentioned methods since the disease causing organisms involved are known to develop natural resistance if only one method of control is applied for a long period of time.